Phantom 4, occasionally twitchy

John Locke · Jul 28, 2016

Occasionally, maybe once in three flights, I have a twitch problem with my P4. I've noticed this since March when I got my first P4. I kinda forgot about this because I have been primarily flying my P3P (due to yoyo of the P4). Now that the P4 yoyo is fixed I'm flying my P4 most the time now, so I'm remembering this and realizing this issue now is not going away.

I will be flying along trying to take buttery smooth video with nice slow movements. In a hover, when I initiate a slow left yaw, instead of the craft slowly yawing to the left the craft yaws to the right at prompt medium speed about 15 degrees. I think this only happens one direction, it's a spontaneous jerk to the right, just as I'm starting left yaw input. It's not easily reproduced, it's a rare occurrence. This kind of behavior totally ruins the shot because of the speed of the yaw in the wrong direction, so I have to do another take. Sometimes this occurs while flying forward also, but most the time it occurs while I'm hovering momentarily. At first I thought it was wind, but most the time it's not windy here in So. Calif. Then I realized I have NEVER had this occur with my P3P, which I've been flying over a year, 1.5mil ft so far.

What's interesting is I've had two P4's. My first P4 had this issue, then it was replaced with a brand new craft when I sent my original to DJI for 3 problems. This replacement craft has the exact same issue. It's a minor issue, but it's annoying.

Has anyone else experienced this behavior?

GadgetGuy · Jul 28, 2016

John Locke said:
Occasionally, maybe once in three flights, I have a twitch problem with my P4. I've noticed this since March when I got my first P4. I kinda forgot about this because I have been primarily flying my P3P (due to yoyo of the P4). Now that the P4 yoyo is fixed I'm flying my P4 most the time now, so I'm remembering this and realizing this issue now is not going away.

I will be flying along trying to take buttery smooth video with nice slow movements. In a hover, when I initiate a slow left yaw, instead of the craft slowly yawing to the left the craft yaws to the right at prompt medium speed about 15 degrees. I think this only happens one direction, it's a spontaneous jerk to the right, just as I'm starting left yaw input. It's not easily reproduced, it's a rare occurrence. This kind of behavior totally ruins the shot because of the speed of the yaw in the wrong direction, so I have to do another take. Sometimes this occurs while flying forward also, but most the time it occurs while I'm hovering momentarily. At first I thought it was wind, but most the time it's not windy here in So. Calif. Then I realized I have NEVER had this occur with my P3P, which I've been flying over a year, 1.5mil ft so far.

What's interesting is I've had two P4's. My first P4 had this issue, then it was replaced with a brand new craft when I sent my original to DJI for 3 problems. This replacement craft has the exact same issue. It's a minor issue, but it's annoying.

Has anyone else experienced this behavior?

I'm having to remember or rediscover all my old P4 settings for expo and gimbal speed for smooth video and such, that were violently overwritten by the latest firmware update. Really annoying. It's going to take me multiple flights to get them all back, since I don't have any record of what they were (I know-- Dumb!) . In the mean time, my flight control is not safe for low ground flying around and between obstacles, that I was just beginning to perfect, before the update. I'm also going to recalibrate the RC sticks, just in case that is part of the problem. Full cold IMU and gimbal calibrations were already done immediately after the update.

DJI should give us a way to safely back up all of our personal settings before any update, and allow us to restore them, immediately after!

jwt873 · Jul 28, 2016

John Locke said:
Has anyone else experienced this behavior?

Yes.. I've noticed it. I was flying today, and coming in for a landing. I nudged the stick the stick left very slightly and the craft yawed to the right a few degrees. It's happened more than once and it is somewhat random. I only notice this when making very slight stick movements to the left. Otherwise the thing flies normally.

Here's a snip from a 30 second video that I took a few days ago. I was following a tree line and touched the stick left to stay on track. When I did the drone yawed to the right.

AIRSPACE · Jul 28, 2016

This happens with my drone too. Descending and yawing left sometimes results in the quad kinda spinning to the right.. I thought it was the propellers so I replaced them but it didn't seem to fix

Sent from my iPhone using PhantomPilots mobile app

GadgetGuy · Jul 28, 2016

I'm now convinced this is the odd control behavior I am experiencing, too! When trying a very slight yaw to the left, to stay on a straight line while flying, it instead yanks it, either in the opposite direction, and now I am in an even worse position than before the attempted correction, or way too far to the left, with no more fine tuning control over direction. Fighting with it several times totally screws up the continuous video as it jitters back and forth, never gently correcting the direction, like before. I have my Yaw expo all the way down to 20%, so this should not be happening.

I recently turned off the Synchronous Gimbal Follow, and maybe that is the culprit? I'll turn it back on and see if that fixes it.

I'm very frustrated, and would much rather have the previous 10 foot drop after coming to a stop, than this odd, video destroying behavior!!

AIRSPACE · Jul 28, 2016

GadgetGuy said:
I'm now convinced this is the odd control behavior I am experiencing, too! When trying a very slight yaw to the left, to stay on a straight line while flying, it instead yanks it, either in the opposite direction, and now I am in an even worse position than before the attempted correction, or way too far to the left, with no more fine tuning control over direction. Fighting with it several times totally screws up the continuous video as it jitters back and forth, never gently correcting the direction, like before. I have my Yaw expo all the way down to 20%, so this should not be happening.

I recently turned off the Synchronous Gimbal Follow, and maybe that is the culprit? I'll turn it back on and see if that fixes it.

I'm very frustrated, and would much rather have the previous 10 foot drop after coming to a stop, than this odd, video destroying behavior!!

Sounds like we are going thru similar. A 10 minute litchi flight ruined by a couple of yaws to stay on course. It is a bit annoying. I also get a little turn when descending manually but when litchi/Dji go app is flying it is definitely less or non existent. I always thought when I was descending I must be nudging the stick.. But maybe it is a software thing

GadgetGuy · Jul 28, 2016

jwt873 said:
Yes.. I've noticed it. I was flying today, and coming in for a landing. I nudged the stick the stick left very slightly and the craft yawed to the right a few degrees. It's happened more than once and it is somewhat random. I only notice this when making very slight stick movements to the left. Otherwise the thing flies normally.

Here's a snip from a 30 second video that I took a few days ago. I was following a tree line and touched the stick left to stay on track. When I did the drone yawed to the right.

That's it. I can't stay on track anymore when trying to follow a straight line like along a street or along the shore. It's better to use the right stick and fly gently sideways to correct the direction. Very annoying. I hope it's only the synchronous gimbal setting that needs to be turned on.

GadgetGuy · Jul 28, 2016

rustlecrowe said:
This happens with my drone too. Descending and yawing left sometimes results in the quad kinda spinning to the right.. I thought it was the propellers so I replaced them but it didn't seem to fix

Sent from my iPhone using PhantomPilots mobile app

I've recently seen yawing and a little instability on a quick descent in place, too.

GadgetGuy · Jul 29, 2016

rustlecrowe said:
Sounds like we are going thru similar. A 10 minute litchi flight ruined by a couple of yaws to stay on course. It is a bit annoying. I also get a little turn when descending manually but when litchi/Dji go app is flying it is definitely less or non existent. I always thought when I was descending I must be nudging the stick.. But maybe it is a software thing

I am hoping that switching to Litchi and waypoint flying will solve all these types of manual flying problems completely. Hopefully, this doesn't affect flying Litchi waypoint missions! That's my future. I'm very impressed with Litchi's capabilities, now that it's on iOS, too!

John Locke · Jul 29, 2016

jwt873 said:
Yes.. I've noticed it. I was flying today, and coming in for a landing. I nudged the stick the stick left very slightly and the craft yawed to the right a few degrees. It's happened more than once and it is somewhat random. I only notice this when making very slight stick movements to the left. Otherwise the thing flies normally.

Here's a snip from a 30 second video that I took a few days ago. I was following a tree line and touched the stick left to stay on track. When I did the drone yawed to the right.

Yep, that looks exactly like what I'm seeing too. I'll post an example of a flight I made today, which convinced me it wasn't the wind. Looks just like your example.

I kinda feel better. It's not my imagination, and its not just my craft. It's another DJI bug in the firmware, I'm convinced. My P3P never does this, it's rock solid in that regard.

UPDATE:
I was wrong, it isn't to yawing left only. It's to the right also. Here's my flight today that I just reviewed and realized this anamoly occurred during a right yaw.
Yaw Flaw

snickell · Jul 29, 2016

GadgetGuy · Jul 29, 2016

#DJI_FixMyYaw!

GadgetGuy · Jul 29, 2016

What does everyone having the problem, have set for their Gimbal Advanced Settings? These are my new settings to try.
I previously had:
Gimbal Tilt SmoothTrack set to 0 and
Enable Synchronized Gimbal Pan Follow set to OFF

jwt873 · Jul 29, 2016

Here are my current settings.. It should be the default. I've never modified anything in the Gimbal options.

ussvertigo · Jul 29, 2016

I ended up modifying my remote as my P2 with a switch and 20 ohm pot on the yaw output, it was the only way I could get the extreme slow and smooth yaw. The stick internal pots could be a lot better. Litchi does help with smooth yaw turns, but I keep the tilt on manual, and have the Tilt SmoothTrack set at 21 for smooth tilts with out sudden stop at end of travel. Tilt Exp is at 50 also, Synch Pan Follow should be "on".

Sent from my iPad using PhantomPilots

GadgetGuy · Jul 29, 2016

ussvertigo said:
I ended up modifying my remote as my P2 with a switch and 20 ohm pot on the yaw output, it was the only way I could get the extreme slow and smooth yaw. The stick internal pots could be a lot better. Litchi does help with smooth yaw turns, but I keep the tilt on manual, and have the Tilt SmoothTrack set at 21 for smooth tilts with out sudden stop at end of travel. Tilt Exp is at 50 also, Synch Pan Follow should be "on".

Sent from my iPad using PhantomPilots

Thanks for the input. The twitch is actually in the opposite direction of the intended adjustment, so reducing the output doesn't help. I'll try your settings! I'm hoping it's just the Synch Pan Follow that I had "off".